Even though it's only been a month since the 2012 rendition of the Coachella Music Festival, organizers have already nailed down the dates for next year's event, and will launch a special one-week advance ticket sales period on Thursday.  Organizers said that this will be the only time that customers will be able to take advantage of the Coachella Purchase Plan.  Coachella 2013 will take place on the weekends of April 12th through the 14th and April 19th through the 21st.  Following the special one-week pre-sale, tickets won't be available until early next year.